Air or gas pump or compressor



2 SheetsSheet 1.

L. R. ALBERGER.

AIR 0R GAS PUMP 0R COMPRESSOR.

(No Model.)

No. 595,429. Patented Dec. 14, 1897.

1 HI lllIHl i IIIII H THE (No Model.) 2 SheetsSheet 2.

L. R. ALBERGER. AIR 0B. GAS PUMP 0R comrmzssonq w No. 595,429. PatentedDec. 14, 1.897.

WZWW UNITED STATES PATENT OFFICE.

LOUIS R. ALBERGER, OF NEW YORK, N. Y., ASSIGNOR TO THE HENRY R.VVORTHINGTON, OF ELIZABETH, NEW JERSEY.

Al R OR GAS PUMP OR COMPRESSOR.

SPECIFICATION forming part of Letters Patent No. 595,429, dated December14, 1897.

Application filed August .1394

'To all whom it may concern.-

citizen of the United States, residing at New York, county of New York,and State of New York, have invented certain new and useful Improvementsin Air or Gas Pumps or Oompressors, fully described and represented inthe following specification and the accompanying drawings, forming apart of the same.

The object of the present invention is to provide an improveddirect-acting air or gas pump or compressor, and especially to providean efficient duplex air pump or compressor of this class. i

In crank and fly-wheel air pumps and compressors the proper movement ofthe plunger throughout the stroke is secured by the flywheel, the excessof power at the beginning of the stroke and until the air on the forceside of the plunger is compressed to delivery- I opposite sides, theplunger mayjump through the first part of the stroke until the pressureon the force side of the plunger is raised to the delivery-pressure,this jump increasing with the ratio of the delivery-pressure to the Isuction-pressure and frequently amounting to more than half a stroke andunder some conditions to nearly a full stroke.

In all direct-acting air pumps and compressors difliiculty has beenfound in securing the uniformity of action desirable to prevent slammingof the valves and shock to the moving parts of the pump, and a dash-potor an additional water-pump actuated by the steampiston of the air pumpor compressor is frequently used for this purpose.

In duplex pumpsthat is, pumps in which the steam-valves on one side areoperated from the other side of the engine, the two pistons and plungersbeing timed differently-each side of the pump opens the steanr valves onthe opposite side in the latter. part of the stroke and usuallycommences to open them only a. little later than half stroke.Consequently if the piston and plunger jump Serial No. 519,560. (Nomodel.)

any considerable portion of the stroke the steam-valves on the oppositeside are opened too early, especially as the blow from the quick motionof the jumping piston will throw the valve and open it in advance of themovement of the piston and valve-rod, and the piston and plunger on theopposite side then jump in turn and again shift the VELIXYGS on thefirst-mentioned side before that side has time to complete its stroke,the result being that the pistons and plungers take short strokes at thecenters of the cylinders, and if the ratios of the delivery-pressure tothe pressure in the cylinder be quite high this stroke may be so shortas to preventthe pump doing any eflective work. This result is aidedalso by the air compressed in the clearance-space, which increases'thepressure behind the plunger and aids in causing the jump referred to,and, moreover, prevents any suction on a very short stroke, as nosuction will take place behind the plunger until the air compressed inthe clearance-space on the previous forward movement of the plunger hasexpanded to suction-pressure. This failure of suction in air-pumpsduring the first part of the stroke, due to the clearance-space, is wellknown, and to avoid this difliculty wet air-pumps have been used andvarious devices employed in dry air-pumps for relieving the pressure inthe clearance-space when the plunger is reversed. This difficulty existsmore largely in direct-acting pumps, because a comparatively largeclearance-space is re quired, while only a small clearance is necessaryin crank and fly-wheel pumps, because the movement of the piston islimited and concussion prevented by the crank. In crank and fly-wheeldry air-pumps also it has been suggested to connect the two oppositeends of the cylinder at the end of each stroke, so as to allow thecompressed air in the clearance-space to expand into the opposite end ofthe cylinder, thus securing suction practically throughout the stroke, avalve construction being used which will prevent the delivery-pressurefrom being transmitted to the force side of the plunger.

I avoid practically all objectionable irregularities of action indirect-acting air pumps or-compressors by making the plunger-loadsubstantially uniform throughout the stroke, and thus am enabled toprovide an eiiicieut duplex air pump or compressor of this class. Thisresult may be secured by admitting pressure on the force side of theplunger from any suitable source at or near the com mencement of eachcompression-strokethat is, so that the plunger shall be undersubstantially the delivery-load at the commencement of the stroke, or soearly in the stroke as to prevent any substantial jump of the plunger. Iprefer, however, to admit the pressure to secure this uniformity of loadwhile the plunger is at rest before reversing, and by connecting thedelivery and pump-cylinder on the force side of the plunger for thispurpose, and I prefer also to connect the two opposite ends of thecylinder at the end of each stroke before communication is thus openedbetween the delivery and cylinder. In attaining this latter result Iemploy an equalizingport which is controlled so as to securecommunication between the opposite ends of the cylinder at the end ofeach stroke, thus permitting the expansion of the air in theclearance-space to the force side of the plunger, so as to lessen thepressure behind the plunger and increase the pressure in front of theplunger at the beginning of the next stroke, these features coacting intending to equalize the plunger-load throughout the stroke. It will beseen that I also secure an advantage in that I thus not only increasethe plunger-load at the beginning of the stroke and so aid in avoidingthe jump previously referred to and in securing the full stroke of theplunger, but I also thus secure suction at the beginning of the stroke,so that even if the stroke of the plunger should be reduced somewhat airwill still be received at the suction end and work done.

The opening and closing of the equalizingport and the control of theconnection between the cylinder ends and delivery to obtain the abovementioned results may be secured by valve constructions of differentform, but I prefer to use a construction in which communication betweenthe delivery and pump-cylinder on the force side of the plunger issecured at or near the com mencement of the stroke through the regularadmission and emission ports at the ends of the cylinder, and theequalizing-port is controlled by the same valve or valves that controlthe delivery, and such a construction forms a part of the invention andmay be employed in single air pumps or compressors as well as in duplexconstructions.

It is evident that the invention may be embodied in constructions ofwidely different form, but for the purpose of illustrating all thefeatures of the invention I have shown in the accompanying drawings,forming a part of this specification, a duplex direct-acting air pump orcompressor which will be found a convenient and efficient embodiment ofthe invention, and a full description of the same Will now be given andthe features forming the invention specifically pointed out in theclaims.

In the drawings, Figure 1 is a side elevation of the pump with thepump-cylinder and valve on one side shown in section. Fig. 2 is a planview of the same.

Referring to said drawings, A B are the two steam-cylinders; O D, thecorresponding pump-cylinders, shown as jacketed for water circulation,as usual; ah, the corresponding piston-rods, and 0 (Z the correspondingplungers. The construction of the steam end of the cylinders and valvemovement is substantially the same as shown and described in many priorpatents, and now well known in connection with the \Vorthington duplexpumping-engine, so that no further description of these parts isrequired, it being understood that the valves on one side of the engineare operated from the opposite side through levers e f, actuated by therespective piston-rods a b and connected to the valves by the usuallinks. It will be understood, however, that any other suitableconstruction may be used for the steam end of the engine, that shownbeing selected only as forming a simple and eflicient construction Welladapted for use in connection with the invention.

At the pump end, E is the suction and F the force main, and G a jointsuction and delivery chamber. This chamber G connects with the suction Ethrough a cove g on each side of the engine and with the opposite endsof the cylinders O D through admission and emission ports h, andcommunication through these ports is controlled on the opposite sides byrotary valves ills, these valves being formed with central ports 1 2,respectively, which connect the ports 71. at the opposite ends of thecylinder when the plunger has reached the end of its stroke, and thusform the equalizing-ports referred to above. These valves 1' 75 areoperated from the opposite. side of the pump by means of the levers ofand links 10 11 on the opposite sides and crank-arms 12 13, carried bythe respective valve-stems.

The positions of the operating parts on both sides of the pump are shownin full and dotted lines in Fig. 1, this figure showing the positionselected for illustration, being that in which the plunger 0 is athalf-stroke and the plunger (Z at the end of its stroke. In thisposition the valve 6 on the c plunger side of the pump is in such aposition as to connect the suction-cove g with the suction side of thecylinder and the delivery with the force side, while the valve on the dplunger side of the pump has closed both the suction and delivery andopened communication through the port 2, between the opposite ends ofthe cylinder D, so that the compressed air in the clearance-space hasexpanded into the opposite end of the cylinder, so as to increase thepressure on the force side of the plunger at the beginning of the nextstroke. The pisforce side of the plunger, so that the delivery--pressure is at once admitted on the opposite side of the plunger and thefull final load upon the plunger secured at the commencement of the nextstroke, thus insuring a uniform action and preventing the jump of theplunger. As the plunger r: reaches the end of its stroke the'plunger don the opposite side of the engine reaches the middle of its stroke andthen commences to shift the valve 2', so as to close the suction anddelivery on that side and to open communication between the oppositeends of the cylinder 0 through the equalizing-port 1, and then to closethe equalizing-port and open the delivery to the opposite end of thecylinder while the plunger c is at rest, and thus the operation iscontinued.

The construction shown, in which a single valve on each side is employedand communication between the delivery and force side of the plunger atthe commencement of the stroke is made through the regular admission andemission ports, is .very simple and emcient and in itself forms a partof the invention; but it will be understood that the invention, broadlyconsidered, may be carried out by other constructions.

It will be understood that the term duplex pump used herein is not to beconstrued as limited to a construction in which there are only twopistons and plungers, but that it is used in its'commercial sense toinclude pumps having two or more steam-cylinders, with their pistons andplungers, and in which the steam valves on each cylinder are operatedfrom the piston of one of the other cylinders, the the pistons andplungers of the different cylinders being timed differently.

What I claim is- 1. A duplex direct-acting air or gas pump provided withmeansfor securing communication between the opposite ends of therespective cylinders at the end of each stroke, and for admitting fluidto the cylinders from another source to increase the pressure in frontof the plungers above the suction-pressure at or near the commencementof each compression stroke, substantially as described.

2. A duplex direct-acting air or gas pump provided with means forsecuring communication between the opposite ends of the respectivecylinders at the end of each stroke and securin g communication betweenthe delivery and the respective. cylinders in front 3. A duplexdirect-acting air or gas pump provided with means for admitting fluid tothe cylinders in front of the plungers at or near the commencement ofeach compressionstroke from a source of pressure substantially equal tothat of the delivery, whereby substantially the delivery-load upon theplunger is secured during the first part of the stroke, substantially asdescribed.

4. A duplex direct-acting air or gas pump provided with means forsecuring communication between the delivery and therespective cylindersin front of the plunger at or near the commencement of eachcompressionstroke, substantially as described.

- 5. The combination with the cylinders and plungers'of a duplexdirect-acting air or gas pump, of delivery-valves constructed andarranged to secure communication between the delivery and the respectivecylinders on the force side of the plungers at or near the commencementof each compression-stroke, and actuating connections between saidvalves and moving parts of the opposite side of the pump, substantiallyas described.

6. The combination with the cylinders and plungers of a duplexdirect-acting air or gas pump, of valves controlling the suction anddelivery, andconstructed and arranged to secure communication betweenthe delivery and cylinders infront of the plungers at or near thecommencement-of each compression-stroke, an equalizing-port on each sideof the pump controlledby said valves and connecting the opposite ends ofthe cylinders at the end of each stroke, and means foractuating thevalves on each side of the pump from the opposite side, substantially asdescribed.

7. The combination with the cylinders and plungers of a duplexdirect-acting air or gas pump, of valves controlling the suction anddelivery, equalizing-ports controlled by said valves, and connectionsbetween said valves and the opposite sides of the pump for actuatingsaid valves to close communication between the delivery and cylinder andopen the equalizing-port at the end of each compres sion-stroke, and toclose the equalizing-port and open communicationbetween the delivery andcylinder on the force side of the plunger before the commencement of thenext compression-stroke, substantially as described.

8. The combination with the cylinder and plunger of a direct-acting airor gaspump, of delivery-valve mechanism constructed and arranged tosecure communication between the delivery and the cylinder on the forceside of the plunger at or near the commencement of thecompression-stroke, actuating connections between said valve mechanismand a moving part of the pump, and an equalizingport controlled by saiddelivery-valve mechanism and connecting the opposite ends of thecylinder at the end of each stroke before the communication between thedelivery and the cylinder is opened, substantially as described.

9. The combination with the cylinder and plunger of a direct-acting airor gas pump, of valve mechanism controlling the suction and delivery, anequalizing-port controlled by said valve mechanism, and connectionsbetween said valve mechanism and a moving part of the pump for actuatingsaid valve mechanism to close communication between the delivery andcylinderin front of the plunger and open the equalizing-port at the endof each stroke, and to close the equalizing-port and open communicationbetween the delivery and cylinder on the force side of the plunger at ornear the commencement of the next compression-stroke, substantially asdescribed.

10. The combination with pump-cylinder C having ports 71, of oscillatingvalve t'provided with equalizing-port 1, and constructed to connectports it through the equalizing-port 1, when the delivery is closed andopen the delivery to one end of the cylinder when the equalizing-port isclosed and at or near the commencement of the compression-stroke, ofactuating connections between said valve and a moving part of the pump,substantially as described.

11. The combination with duplex pumpcylinders O, D having ports 7L, ofoscillating valves 6, 70 provided with equalizing-ports 1,2,

and constructed to connect ports h through the equalizing-ports 1, 2 inthe respective cylinders when the delivery is closed and open thedelivery to one end of the cylinder when the equalizing-port is closedand at or near the commencement of the compression-stroke, of actuatingconnections between each of said valves and the opposite side of thepump, substantially as described.

12. The combination with duplex pumpcylinders O, D having ports h, ofoscillating valves 2', 7c, controlling said ports, and connectionsbetween said valves and the opposite sides of the pump for shifting saidvalves to open the delivery on the force side of the plunger for thenext stroke before the stroke is commenced, substantially as described.

13. The combination with duplex pumpcylinders C, D having ports h, ofoscillating valves 2', 7c, controlling said ports, and havingequalizing-ports 1, 2, and constructed to connect ports 7L through theequalizing-ports when the delivery is closed, and connections betweensaid valves and the opposite sides of the pump whereby said valves areactuated, substantially as described.

In testimony whereof I have hereunto set my hand in the presence of twosubscribing witnesses.

LOUIS R. ALBERGER.

Witnesses:

C. J. SAVVYER, T. F. KEHOE.

